Several shops and houses of rival leaders and workers were attacked over the Sabarimala issue on Saturday, as violence involving BJP-RSS and ruling CPI(M) rocked parts of Kerala, particularly Kannur district. Besides Kannur, Perambra in neighbouring Kozhikode, Malappuram and Adoor in Pathanamthitta, where the Ayyappa shrine is located, also witnessed a series of similar attacks and vandalism Friday night and early Saturday.